Adaptor for a magazine



July 1, 1958 J. F. THOMPSON 2,840,944

' ADAPTOR FOR A MAGAZINE Filed March 30, 1954 I9 20 FIG. I. 26

A INVENTOR JAMES F THOMPSON BY '2 I ATTORNEYS United StatC tfimio FADAPTOR FOR A MAGAZINE James F. Thompson, Chester-town, Md. ApplicationMarch 30, 1954, Serial No. 419,665 1 Claim. (Cl. 42--50) This inventionis an improvement in the art of producmg firearms, and moreparticularly, the conversion of firearms originally designed to fire asolid projectile, into firearms designed to fire a shot containingcartridge.

It is an object of this invention to produce a cartridge that is loadedwith shot using the standard case that is made to contain a solidprojectile.

It is another object of this invention to convert automatic rifles andpistols, originally designed to fire a solid projectile into a gun thatwill fire shot, particularly automatic firearms having a magazine feed.

Automatic pistols such as the 45 Colt, now a standard "A charge 32 of125 grains of 7 /2 shot are 2,840,944 fi a e 't s r ly}, ras s case aprimer 31 is used to fit this case. The case is then cupped wad 32slightly compressing the powder. On top of the cupped wad is a metalshim wad about 7 of an inch thick. On top of that is a compressiblelubricating wad, the most desirable being a thin waxed felt wad about ofan inch thick. This is followed by a gripper wad to prevent sticking ofthe shot to the lubricating wad. held in place by means of a top Waxedwad. 4 e

Referring specifically to Fig. 9 the same case is used as describedabove with the same primer, the powder charge 33 being placed below thesolid projectile 34.

When it is desired to fire a shot containing cartridge wherein the caseis no longer than the solid projectile case, normally used withautomatic weapons, it is necesweapon for the armed forces canbeconverted to automatically fire shot containing shells in accordancewith this invention by placing the adaptor in the magazine, said adaptorbeing so constructed that it will guide the shot containing shell intothe chamber in the barrel. Without this adaptor the automatic feedmagazine will jam before the shell enters the chamber. This isparticularly true of the Colt automatic pistol. Broadly, this applies toany rifle or pistol having a magazine in which the cartridge is fed intothe chamber by means of a'magazine having a spring actuated follower toforce the cartridge into the loading position.

This adaptor is also applicable to automatic rifles such as the .30calibre carbine and the German automatic G 53 or to any automatic riflethat is fed from a spring actuated magazine.

These magazine fed arms of either the pistol or rifle type may be usedto fire a shot containing shell automatically, if the shell can be madeto fit in the magazine bebind the chamber, using the cartridge case thatis designed to hold the solid projectile only if some means isintroduced to compensate for the shortened cartridge. The

sary to place an adaptor within the magazine to'compensate for thereduced length of the shell andat the-same time to ensure proper feedingof the shortened shell into the chamber. The device used to ensureproper feeding of the shell is the extended end of the adaptor whichadaptor 11 is placed in the forward edge of the magazine 10 andcompensates as stated above forthe shortened shell. The follower 12 isforced upwardly by the spring 13 which extends around the forward edgeof the cutback adaptor and is of the same size as is manufactured forthe particular weapon being converted by means 'ofthe adaptor. Thisadaptor is held in place by the notch 14 in the bottom'thereof, shown inFig. 6 whichfits over the magazine bottom plate bars 15 across the baseof the magazine shown in Fig. l and is retained at its top by a loadedshell is then not as long as it was originally intended and an adaptormust be placed in the magazine to ensure proper feeding in order tomaintain automatic operation. This adaptor must do more than compensatein the magazine for the shortened shell. It must also ensure properautomatic feeding of the shell into the chamher.

One embodiment of this invention is shown in the attached drawing,wherein:

Fig. 1 is a sectionalized view of an automatic pistol containing amagazine;

Fig. 2 is an end view of the magazine;

Fig. 3 is a side view of the magazine;

Fig. 4 is a plan view of the magazine;

Fig. 5 is a plan view of the adaptor;

Fig. 6 is a side view of the adaptor;

Fig. 7 is a sectionalized view of the magazine showing the secondmodification of this invention;

Fig. 8 is a sectionalized view of a shot containing cartridge; and

Fig. 9 is a sectionalized view of a solid projectile containingcartridge.

In loading a shot containing shell a .45 auto-government metal case 30(Fig. 8) is used. With the standard pin 16 through the magazine whichgoes through the hole 17 shown in the adaptor in Fig. 6. This adaptorhas an extended top 18 shown in Figs. 5 and 6, which-extends flush withthe outside of the magazine as shown in Figi 3, so as to force the shellupwardly during the feeding operation, later described, and ensuresproper loading o'fthe shell into the chamber 19. This chamber has ashoulder 20 extending across the' top thereof and aT'bevell'edpor tion21. -The groove of the face of the part 18 of the adaptor is so arrangedas to force the shell upwardly during the loading operation so that itwill contact the bevelled portion 21 and enter the chamber 19 properly.

The adaptor having the shank 22 in the upper part 18 has a shoulder 23which over-rides the edge of the magazine shown in Figs. 2 and 3. Thisshoulder allows the adaptor to come flush and continues the straightforward edge of the magazine upwardly. The part 18 of the adaptor alsohas a rear face which contacts the shell during the loading operation.It must have a cut-away part 24 on the side thereof to allow the slidestop to clear the adaptor.

A second form of adaptor is the follower 12 is forced upwardly by meansof the spring 13, which spring is narrower than the spring originallymanufactured for the magazine and does not surround the adaptor shank 22but rests against the rear edge thereof and forces the follower andshell upwardly in the magazine. magazine in the same manner as is thatshown in the first form.

In operation the magazine is equipped with an adaptor The slide 26 isretracted against the recoil spring 29 and when released the recoilspring forces the slide forward into a closed position. As the slidestarts to close the lower edge of the breech block contacts the upperedge shown in Fig. 7 wherein This adaptor is held in'place in the a a as of the rear of the cartridge. The groove on the side of the casecontacts the extractor. The forward edge of the case is guided by theface of the adaptor, referred to rabove,- s that it "comesinto :contactwith the bevelled lower edge 21 of the chamber and'is guidedintothechamber when the slide is moving to the forward posi- ;tion. The pistonis then ready for firing. On firing, the usual automatic operation isperformed as described :above.

The gas generated in the cartridge fired in the pistol is utilized toperform the function of extracting and ejecting the empty cartridgecase, cocking the hammer and forcing the slide to the rearward position,thereby compressing the recoil spring. The action of the recoil springforces the slide forward, feeding a live cartridge from the magazineinto the chamber, leaving the weapon ready for firing again.

The top face of the adaptor is bevelled to give a ramp along which thecase slides during the loading operation to prevent the case fromtilting outwardly or sideways which would produce a jam. This ramp is anessential feature of this invention. The face of this ramp has a groovecut in it that helps guide the shell into the chamber. This groove isdesirable, but is not a necessary feature, as the face of the ramp shownin Fig. 3 does not have said groove. This groove 26 is shown on the faceof the adaptor in Figure 7.

In the second modification shown in Fig. 7, the forward edge of theshank 22 comes into contact with the inside of the plate forming themagazine, and it is desirable to cut a small groove 27 therein to takethe retaining latch 25, which holds the magazine in place in the pistonagainst the compression of the magazine spring operating through the topcartridge.

It 'has often been found desirable to fire shot from an automatic weaponinstead of the solid projectile designed to operate in the weapon and itis also desirable when using the weapon in this manner to use a standardcartridge case designed to hold the solid projectile. This allows theuse of the weapon to kill small animals, which is of the utmostimportance in the survival of armed personnel in hostile and uninhabitedterritory. Itis also desirable in the training of personnel in handlingautomatic weapons to use a shell containing shot so that the usual claytargets may be used to bring the personnel into greater familiarity withthe weapon and to teach rapid swinging and aiming of the weapon, whichis impossible with a stationary target, now commonly used. This adaptorallows the use of each individuals own weapon, using a magazinecontaining the adaptor in the gun When automatically firing a shotcontaining shell in such a manner 'thathe can readily acquire ahighdegree of skill in handling his weapon. Heretofore adaptors have beenplaced in a repeating weapon to compensate for shorter loads buttheautomatic loading feature found in the adaptor described above hasnot been heretofore used. This adaptor is the first to present a simpledevice that may be added to a standard weapon to allow its conversion sothat shorter cartridges may be fired therefrom.

What is claimed is:

An adaptor to fit in the forward edge of a magazine of an automaticfirearm, said tmagazine comprising a spring and follower and saidfirearm comprising a bolt and chamber, the adaptor comprising a shankportion and a ramp portion, said shank portion extending the length ofthe magazine and lying entirely within the spring and in front of thefollower, the bottom end of the shank having a notch fitting over aplate bar in the bottom of the magazine, the top end of the shank beingheld in place by means of a pin through the magazine walls; the ramp, anextension of the shank, overlying the edge of the magazine andterminating below the bolt and having an inclined concave surfaceleading to the chamber.

References Cited in the file of this patent UNITED STATES PATENTS875,762 'Winans et a1 Jan. 7, 1908 1,401,152 Green Dec. 27, 19211,407,633 Burton Feb. 21, 1922 2,144,232 Spengler Jan. 17, .19392,296,729 Moss'berg Sept. 22, 1942 2,507,364 Benson May 9, 1950 FOREIGNPATENTS 634,724 Germany Sept. 2, 1936

